Morphologic characterization of the patent ductus arteriosus in the premature infant and the choice of transcatheter occlusion device

Objectives : The aim of this study was to describe and differentiate the morphology of patent ductus arteriosus (PDA) seen in children born prematurely from other PDA types. Background : PDAs are currently classified as types A‐E using the Krichenko's classification. Children born prematurely with a PDA morphology that did not fit this classification were described as Type F PDA. Methods : A review of 100 consecutive children who underwent transcatheter device closure of PDA was performed. The diameter and length ( L ) of the PDA and the device diameter ( D ) were indexed to the descending aorta (DA) diameter. Results : Comparison of 26 Type F PDAs was performed against, 29 Type A, 7 Type C and 32 Type E PDAs. Children with Type F PDAs (median 27.5 weeks gestation) were younger during the device occlusion compared with types A, C, and E (median age: 6 vs. 32, 11, and 42 months; P  = 0.002). Type F PDAs were longer and larger, requiring a relatively large device for occlusion than types A, C, and E (Mean L/DA: 1.88 vs. 0.9, 1.21, and 0.89, P  ≤ 0.01 and Mean D/DA: 1.04 vs. 0.46, 0.87, and 0.34, P ≤0.01). The Amplatzer vascular plug‐II (AVP‐II) was preferred for occlusion of Type F PDAs (85%; P <0.001). Conclusions : Children born prematurely have relatively larger and longer PDAs. These “fetal type PDAs” are best classified separately. We propose to classify them as Type F PDAs to add to types A‐E currently in use. The AVP‐II was effective in occluding Type F PDAs. © 2015 Wiley Periodicals, Inc.